What is the basic purpose of having leap years?
A) to keep the equinoxes and solstices occurring around the same calendar dates each year
B) to keep lunar calendars roughly synchronized with solar calendars
C) to make sure that the average length of a solar day remains about 24 hours
D) to ensure that there are always 12 months in a year
A) to keep the equinoxes and solstices occurring around the same calendar dates each year
You might also like to view...
Projectile Motion: In a room where g = 9.81 m/s2, a hockey puck slides off the edge of a platform with an initial velocity of 28.0 m/s horizontally. The height of the platform above the ground is 2.00 m. What is the speed of the puck just before it hits the ground? The air resistance is negligibly small.
A. 48.2 m/s B. 28.7 m/s C. 28.0 m/s D. 26.3 m/s E. 6.26 m/s
A horse pulls a 350-kg sled at constant speed along an icy road for a distance of 500 m. If the coefficient of kinetic friction between the sled and the road is 0.450, and the angle between the harness and the sled is 25°, what is the mechanical energy lost due to friction?
a. –9.8E+5 J b. –6.4E+5 J c. –1.3E+3 J d. –7.4E+3 J
A projectile is shot horizontally at 23.4 m/s from the roof of a building 55 m tall and experiences negligible air resistance. (a) Determine the time necessary for the projectile to reach the ground below
(b) Determine the distance from the base of the building that the projectile lands. (c) Determine the horizontal and vertical components of the velocity just before the projectile reaches the ground.
What type of volcano forms a layered, composite cone?
a. Fumarole b. Cinder cone c. Stratovolcano d. Shield volcano